Squaring Numbers ending in 2

Squaring Numbers ending in 2
To square the numbers ending in 2 like 12, 22,32, 42 .upto 92. there is an easy method let me explain with an example.

1^st example 12²

step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
1²=1
2²=4
step 2 : multiply the tens digit of the number to be squared to 4 and it will be the tens digit of the square
here 1x4 =4
1 4 +
  4
---------
144
---------
so the square of 12 is 144.

2^nd example 42²
step 1 : Split the 2 digits of the number and square each digit to make the ones' place and 100th place respectively of the square
4²=16
2²=4
step 2 : multiply the tens digit of the number to be squared to 4 and it will be the tens digit of the square
here 4x4 =16
16  4+
  16
-------------
1764
-------------
so 42²=1764